Often, a large number of semiconductor devices, such MOSFETs (Metal Oxide Semiconductor Field-Effect Transistors) or IGBTs (Insulated-Gate Bipolar Transistors), is integrated in the same semiconductor body. Often it is desirable to make a distance between two neighboring devices as low as possible in order to be able to integrate as many semiconductor devices as possible in a given area of the semiconductor body. It is therefore necessary to form insulation structures between adjacent devices, to provide electrical isolation between them. Such an insulation structure may include a deep narrow trench that is etched into the semiconductor body and is filled with an oxide.
There is a need to provide an insulation structure that provides effective isolation between semiconductor devices integrated in the same semiconductor body and that can be implemented in a space-saving manner.